1. Technical Field
The present invention relates to a polymerizable composition for an optical material, and more particularly, to a polymerizable composition for an optical material containing a specific polyisocyanate and a specific polythiol compound. The invention also relates to an optical material obtainable from this polymerizable composition for an optical material, and a method for producing this optical material.
2. Related Art
Plastic materials have been traditionally used as a substituent for inorganic materials in the application of optical parts. These plastic materials are lightweight and are not susceptible to breakage, and can be tinted, as compared with the inorganic materials that have hitherto been used. Therefore, plastic materials are being preferentially used. Particularly, plastic materials having high refractive index are desirable for optical parts such as lenses, and suggested examples of such plastic materials having high refractive index include sulfur-containing urethane (thiourethane) resins described in Japanese Unexamined Patent Publication Nos. H02-153302 (1990-153302), H01-295202 (1989-295202), H02-000802 (1990-000802), S63-046213 (1988-046213), S64-045611 (1989-045611).